Horse Fly Larva, we believe

Subject:  Beauty and a beast
Geographic location of the bug:  Nova Scotia, Canada
Date: 07/19/2018
Time: 05:41 AM EDT
Your letter to the bugman:  Hi Bugman!
I was recently working on stream habitat assessments …  On another day, we were looking at rocks for freshwater benthic macroinvertaebrates and I found this worm-like creature that was not on our super-simplified ID guide. It was translucent and you could see everything shifting around when it moved. As I was trying to take photos and video of it moving/wriggling, it bit me (or stung/poked me), drawing blood and I dropped it. Luckily (or unluckily depending on how you look at it, I suppose), we came across another one later. As I watched it move this time, I believe what I might have gotten stuck with its back end grippers which it seems to use to grip onto the rock face. I was looking at some other aquatic larval stages for different insects and cam across an image of crane fly larvae that looks similar, but again, I’m not really sure and was hoping you might have a better idea.
Here’s hoping!
How you want your letter signed:  Many thanks, Van

Horse Fly Larva

Hi Van,
We believe your guess that this is a Crane Fly larva is incorrect, but we do believe you have the insect order correct.  We believe this is an aquatic Horse Fly larva and according to the Missouri Department of Conservation:  “The larvae of horse and deer flies are fairly straight, segmented, wormlike maggots that are tan, whitish, or brownish. Several fleshy rings circle the body. They are robust, circular in cross-section, and taper at both ends. There are no true legs, although fleshy, nobby pseudopods or prolegs are present. In relaxed specimens, a thin, pointed breathing tube extends from the hind end to protrude above the water surface.”  BugGuide has an account of a person being bitten by a Horse Fly larva.

Horse Fly Larva
Thanks Daniel!
Go figure, the horse flies are still jerks even before they grow up 😀
Thanks for the help.

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